[RESEND PATCH 0/2] iowait and idle fixes in /proc/stat

From: Tom Hromatka
Date: Wed Sep 09 2020 - 14:37:32 EST

A customer is using /proc/stat to track cpu usage in a VM and noted
that the iowait and idle times behave strangely when a cpu goes
offline and comes back online.

This patchset addresses two issues that can cause iowait and idle
to fluctuate up and down. With these changes, cpu iowait and idle
now only monotonically increase.

Tom Hromatka (2):
tick-sched: Do not clear the iowait and idle times
/proc/stat: Simplify iowait and idle calculations when cpu is offline

fs/proc/stat.c | 24 ++++++------------------
kernel/time/tick-sched.c | 9 +++++++++
2 files changed, 15 insertions(+), 18 deletions(-)